Post-mortem on recent storm

If we’re looking at this like a medical disorder, we can examine the symptoms and the root of the problem with this storm.

The symptoms of the illness were the following:

1) Progressive, unorganized trough, in which some of the H5 vort energy ran out ahead of the energy rounding the base of the trough. As a result, the energy couldn’t congeal and acquire a negative tilt. Instead, the lead H5 vort energy remained fairly neutral tilted which screams fast-moving, late developing coastal low. These tend to favor eastern New England due to longitude help.

2) The progressive unorganized H5 energy within the trough and lack of neg tilt caused an energy transfer that was too little too late for us. The 925MB low was still transfering from PA as precip was wrapping up in NJ. This is no good. When I looked at 925 winds yesterday around 1pm, and they were still SELY into PA, I knew we were dead in the water. You simply can’t have any warm tongue contamination from the sfc-850mb in thr NYC/coast. It’s a reason why the interior has a higher avg snowfall than us. We need more stars to align for a SECS event. Some people elsewhere were talking about how 850’s were conducive for all snow, but this event was a perfect example of why short term soundings are important, especially in energy transfers, there’s bound to be p-type problems on the coastal plain.

Tracing the symptoms back to the ultimate illness…

A) The trough on the West Coast kept wavelengths rather short, and the central Plains mid level ridge was too far east of the ideal Boise ID position for an amplified/neg tilted nor’easter on the east coast. The trough there did teleconnect to a fast moving / progressive, late developer for the Northeast coast. The lack of a decent PNA ridge definitely hurt us, as more amplification in the Western US would have resulted in a slower downstream pattern, meaning a deeper / more amplified trough, more organized H5 energy, and thus a higher likelihood for negative tilting and bombing on the mid atlantic coast.

We’ve seen winters with snowy with a -PNA overall but it makes sense meteorologically that you would want a ridge in the Western US in order to get a deep trough and bombogenesis on the East Coast. Low amplitude or non existant Western ridging results mostly in SWF events, and late bloomers, favoring eastern New England due to longitude once again. A stronger -NAO probably would have helped slow the pattern down but we didn’t have that either.

Ultimately it’s the progressive nature of the pattern that killed us here, and that’s largely due to the upstream lack of ridging on the West Coast, which will be fixed in the coming days as the PNA spikes. Problem now is the polar vortex in SE Canada might crush everything south of us.